Collapsible link

ABSTRACT

A collapsible link of simple construction wherein transverse members have axial recesses which interengage with one another at separated points along the axis of the link. A key member insertable into the link, is adapted to prevent the accidental disengagement of the elements of the link.

Umted States Patent [151 3,704,902

Moore, Sr. et a1. Dec. 5, 1972 I541 COLLAPSIBLE LINK 2,554,876 5/1951 Olson ..287/103 R Inventors: Geo ge dward Moore Sr; G orge Harrall et a1 R Moore, Jr. of Morae R Mundy Street, Coquitlam, British FOREIGN PATENTS OR APPLICATIONS Columbia, Canada 132,745 8/1951 Sweden ..287/103 R [22] Filed: Nov. 25, 1970 [2]] Appl. N0.: 92,654 Primary Examiner-Andrew V. Kundrat Att0meyBurns, Doane, Swecker & Mathis [52] US. Cl ....,287/64, 287/99 57 ABSTRACT [51] Int. Cl ..Fl6d 19/00 A [58] Field of Search. "287/64 99 R; 59/78 A collapsible link of simple construction wherein transverse members have axial recesses which interengage with one another at separated points along [56] References Cited the axis of the link. A key member insertable into the UNITED STATES PATENTS I link, is adapted to prevent the accidental disengage- 1 ment of the elements of the link. 1,098,018 5/1914 Cook .237/103 R 1,272,131 7/1918 Silberg ..287/103 R 11 Claims, 7 Drawing Figures 1 \l 3 l I I l I up 1 3 2 I 2 L lllll 'l llii PATENTEDuEc 5 i922 PATENTEmEc' s 1922 3 7 04. 902

' sum 2 or 4 COLLAPSIBLE LINK The present invention relates to a general purpose collapsible link.

Although numerous types of links are in use at the present time, most links are constructed in such a manner that the elements interconnect only at a single locationalong the axis of the link. As a result, such links are often unreliable in use or require additional supporting elements to provide the necessary rigidity. Moreover, because of their complexity, most of these links are relatively expensive to manufacture and include separable components which may become lost or broken.

Accordingly, it is an object of the present invention to provide a linkwhich is collapsible and at the same time has a high degree of rigidity.

It is a further object of the present invention to provide a multi-purpose link, the elements of which are adapted to interlock at spaced locations along the axis.

It is a still further object of the present invention to provide a link of simple construction having few components.

It is a still further object of the present invention to provide a link particularly adapted to carry a compressive load.

It is a still further object of the present invention to provide a means which may be used to prevent the accidental separation of the elements of the link while they are interlocked.

The collapsible link in accordance with the present invention includes a first and a second element adapted to engage one another at two spaced locations along the axis of the link.

In accordance with the present invention, the collapsiblelink includes a first and a second element, each of said first and said second elements has a first and a second recess spaced along the axis thereof, said first recess on said first element is adapted to interlock with said second recess on said second element and said second recess in said first element is adapted to interlock withsaid first recess on said second element.

A further embodiment of the present invention includes a key means adapted to be inserted between the links to prevent accidental separation of the interlocking elements of the link.

FIG. I is a perspective view of a link in accordance with the present invention in its interlocked position;

FIG. 2 is a top view of one of the elements of the link shown in FIG. I;

FIG. 3 is a perspective view of a key and pin adapted for use with the link shown in FIG. 1;

FIG. 4 is a top view of the link fitted with the key shown in FIG. 3;

FIG. 5 is an example of one possible application of the link in accordance with the present invention;

FIG. 6 is a side elevation partly in section of an alternative embodiment of the key; and

FIG. 7 is atop view partly in section of an alternative embodiment of the link.

Referring now to FIG. 2, which shows one of the elements of the link, one end of axially extending connecting member 2 is adapted to be fixed to the apparatus with which the link is to be used. The other end of connecting member 2 is joined to transversely extending member 3. Transversely extending members 3 and 6 are of rectangular cross sections and are joined to one another by members 9 and 10. Recesses 4 and 5 in members 3 and 6 respectively are situated at the axis of the element. As shown in FIG. 2, recess 4 is bounded by bottom wall 20 and side walls 19 and 21. Similarly,

recess 5 is bounded by bottom wall 23 and side walls 22 and 24. It is to be noted that the cross sections of the members which make up the elements may be T- shaped rather than rectangular as shown in the drawings.

Referring now to FIG. 1, which shows the two elements of the link in the interconnected or interlocked position, the link 25 comprises two identical interlinked elements of the type shown in FIG. 2, indicated generally as l and l in FIG. 1. These elements may be fabricated with one side open using a punch press to shape the elements. After interlinking the two elements, the opened sides may be closed and then welded. Alternatively, it may be feasible in some cases to cast the two elements of the link using interlocking castings. The link may be made of any suitable material such as plastic or metal.

As shown in FIG. 1, when the link is in the interconnected position, the axial recess in member 3 engages the axial recess in member 6 so that the bottom walls of these recesses abut. The side walls of these recesses snugly engage opposite surfaces of the other element adjacent the recess. Similarly, the axial recess in member 3 engages the axial recess in member 6' so that the bottom walls of the recesses abut and the side walls snugly engage opposite surfaces of the other element.

It will be appreciated that the relative dimensions of the members 3 and 6 and recesses 4 and 5 may be varied to obtain the required tightness of fit between the elements of the link, in accordance with the use to which the link is to be applied.

Referring now to FIG. 3, the key 50 comprises an insertable portion 55 and projecting shoulder portions 51 and 53 on 55. An opening 54 in the insert portion 55 is adapted to receive pin 52.

In order to place the link in its interlocked position, the axes of the two elements are aligned, while the planes of the elements are perpendicular to one another, and an axial compressive force is applied to the elements. If it is desired to obtain a connection which cannot be collapsed accidentally, key 50 is inserted through the openings in the interlocked links 1' and l and pin 52 is inserted into opening 54 in the key 50, as shown in FIG. 4. In order to collapse the link, the foregoing procedure is reversed.

FIG. 5 shows one possible application of the present invention wherein a link 25 in accordance with the present invention is used to collapsibly connect leg 15 to table top 16. As shown in FIG. 5, link 25 may be used to provide a rigid coupling between leg 15 and table top 16 while permitting leg 15, if desired, to be collapsed and folded against table top 16.

An alternative embodiment of the invention is shown in FIG. 7. In this embodiment the two elements of the link are prevented from accidental separation by means of a spring loaded ball 61 which fits into recess 64. As shown in FIG. 7, spring 62 presses against the ball 61 so that part of the ball extends into recess 64 through an opening in wall 22 which is of smaller diameter than the ball. The compression of spring 62 may be adjusted by means of set screw 63. Recess 64 in the member 3' is adapted to receive the projecting portion of the ball 22 when the two elements are interlocking to thereby prevent accidental separation of the elements. This embodiment is particularly suited for light duty applications.

FIG. 6 shows an alternative embodiment of the key 50 wherein spring loaded pins 71 and 72 are an integral part of the key. This key may be readily inserted or removed from the interlocking elements of the link simply by pressing the pins 71 and 72 into the body of the key and then inserting or removing the key.

Numerous applications of the present invention are contemplated. The link is particularly suited for supporting loads requiring legs, such as tables, furniture, camping equipment, bunk beds, portable machinery supports, sawhorses, etc. The link could also be used to support marine masts, emergency antennas, truck and railway car stakes and laundry drying equipment.

Numerous variations and modifications may obviously be made without departing from the scope and concept of the present invention. Accordingly, it should be clearly understood that those forms of the present invention which are described herein, and which are depicted in the figures of the accompanying drawings, are illustrative only and are not intended to limit the scope of this invention.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

l. A collapsible link device including a first and a second element, said first and second elements each comprising a first and a second spaced member situated perpendicular to the axis of the element and in a common plane, a recess in each of said members situated at the axis of said element, said recess in said first member of said first element adapted to snugly interlock with said recess in said second member of said second element and said recess in said second member of said first element adapted to snugly interlock with said recess in said first member of said second element, when said second element is situated in a plane perpendicular to the plane of said first element.

2. A device in accordance with claim 1 wherein each element includes a connecting member situated along the axis of said element and joined to said first member.

3. A device in accordance with claim 1 wherein said recesses are rectangular and said first and second members are of rectangular cross sections.

4. A device in accordance with claim 1 wherein said first and said second elements are interlinked.

5. A device in accordance with claim 4 wherein each of said recesses is bounded by an end wall and two side walls, the end walls of said interlocking recesses adapted to abut one another and said side walls are adapted to engage the other element.

6. A device in accordance with claim 4 including a key adapted to be inserted through said elements to prevent their accidental separation.

7. A device in accordance with claim 1 including a key adapted to be inserted through said elements to prevent their accidental separation and a pin insertable into said key to thereby prevent removal of said key.

8. A device in accordance with claim 2 wherein said recesses engage one another in pairs at spaced locations alongtheaxis of the link.

9. A device in accordance with claim 6 wherein said key includes spring loaded pins adapted to prevent accidental removal of said key from said interlocking elements.

10. A device in accordance with claim 1 wherein said first and second members are of T-shaped cross sections.

11. A device in accordance with claim 2 wherein said recesses are rectangular and said first and second members are of rectangular cross-sections. 

1. A collapsible link device including a first and a second element, said first and second elements each comprising a first and a second spaced member situated perpendicular to the axis of the element and in a common plane, a recess in each of said members situated at the axis of said element, said recess in said first member of said first element adapted to snugly interlock with said recess in said second member of said second element and said recess in said second member of said first element adapted to snugly interlock with said recess in said first member of said second element, when said second element is situated in a plane perpendicular to the plane of said first element.
 2. A device in accordance with claim 1 wherein each element includes a connecting member situated along the axis of said element and joined to said first member.
 3. A device in accordance with claim 1 wherein said recesses are rectangular and said first and second members are of rectangular cross sections.
 4. A device in accordance with claim 1 wherein said first and said second elements are interlinked.
 5. A device in accordance with claim 4 wherein each of said recesses is bounded by an end wall and two side walls, the end walls of said interlocking recesses adapted to abut one another and said side walls are adapted to engage the other element.
 6. A device in accordance with claim 4 including a key adapted to be inserted through said elements to prevent their accidental separation.
 7. A device in accordance with claim 1 including a key adapted to be inserted through said elements to prevent their accidental separation and a pin insertable into said key to thereby prevent removal of said key.
 8. A device in accordance with claim 2 wherein said recesses engage one another in pairs at spaced locations along the axis of the link.
 9. A device in accordance with claim 6 wherein said key includes spring loaded pins adapted to prevent accidental removal of said key from said interlocking elements.
 10. A device in accordance with claim 1 wherein said first and second members are of T-shaped cross sections.
 11. A device in accordance with claim 2 wherein said recesses are rectangular and said first and second members are of rectangular cross-sections. 